The present invention generally relates to automatic appliances. More particularly, the invention relates to a diagnostic system for an automatic appliance. Yet more specifically, the invention relates to a diagnostic system for an automatic washer.
There is always a possibility that an appliance may malfunction during use during its lifetime. The malfunction may be minor or major. A minor malfunction is likely to be easily rectified, many times by persons not skilled in the repair of appliances, as only minor adjustments to the appliance may be required. Further, in certain instances, the appliance may continue to operate unimpeded despite the minor malfunction. On the other hand, it is likely that a major malfunction can only be rectified by someone skilled in the repair of that particular appliance and that a major malfunction will force operation of the appliance to discontinue.
With the advent of the lowering cost and size of electronic sensors, and other related electronic products, it is possible to employ sensors and related electronics in appliances to provide data that can be helpful in diagnosing the causes of a malfunction. To this end, several diagnostic systems have been employed in automatic appliances. These systems store data for subsequent retrieval for analysis to determine the cause of a malfunction or operational error.
A diagnostic system is a system designed to implant a diagnostic routine, wherein a series of steps are undertaken to locate and identify any malfunction. Typically, in computer based diagnostic systems, a program is executed and a series of electronic elements are queried by the system to determine if any is exhibiting a state of malfunction. The electronic elements can include sensors and/or other elements such as portions of the computer.
U.S. Pat. No. 4,630,191 discloses an automatic round or roll baler having an operator controlled system. Therein, a central system includes a microprocessor controlled signal processing circuit that is responsive to signals derived from various switches for controlling the wrapping of a bale and signalling to an operator the status of the baler. The diagnostic system can be initiated by the operator from a control panel. An operator's manual leads the operator through a series of successive test steps, such as actuating switches, and the signal processor visually and audibly signals the operator as to whether or not the test step was successful.
U.S. Pat. No. 4,498,130 discloses a microprocessor controlled copying machine having a self diagnosis capability. The diagnosis operation start and stop instruction signals can be applied from either a front control panel or from remote operating switches, with one or the other instruction signals being selected to control a respective output terminal or machine component.
U.S. Pat. No. 4,245,309 discloses a microprocessor based control circuit for an automatic washer having a diagnostic system. The control circuit responds to user selected options to determine the operating sequence of the washer. Feedback systems provide detection and indication of fault conditions such as overfill and drain blockage, and initiate protective measures to prevent damage to the appliance. A diagnostic system routine is employed to sequence through the usual operating cycles in response to operator input and advance therethrough at the operator's discretion.
Operative cycle and appliance malfunctions, if any, are displayed on the control panel as the diagnostic routine is executed.
U.S. Pat. No. 4,158,432 discloses a self test feature for appliances that is embodied in a microprocessor controlled microwave oven. The self test feature is actuated through the microwave oven keypad and causes the system to sequence through test routines whereby a series of light emitting diodes of an alphanumeric display are illuminated in a predetermined order, each digit of the display counting up from 0 to 9. Keypad inputs are displayed as codes.
U.S. Pat. No. 3,939,453 discloses a diagnostic display for a machine sequence controller for an automatic grinding machine. The sequence controller controls a sequence of machine functions and provides a digital display of information, including diagnostic information. Diagnostic information is displayed on two levels. The first level is defined as "input code" which represents signals generated by a programmable controller to define the machine requirements due at a given time. These signals are compared with signals defining requirements met from input devices to determine if the sequence should be allowed to advance. The second level is defined as "cycle step commands" which represents signals sequentially generated by the controller to actuate specific machine functions. The controller can advance sequentially or non-sequentially. Circuit boards are correlated in physical location to cycle step command codes.
It would be advantageous to provide an automatic appliance, such as an automatic washer, with a diagnostic system wherein data is stored for later retrieval for analysis, and wherein the system, in identifying the fault, determines whether the fault is grave enough so as to require the need for experienced repair personnel to correct the fault. In so doing, the system can be employed so as to store data available to the skilled repair person, which data is retrievable from the normal control panel with a simple adaptive device such as an overlaying template.